Dental wedges are well known in the art and have been used extensively for over a century. As is well known, each tooth ideally contacts the next only at the top surfaces thereof. When repairs are needed on a tooth, the tooth is separated from adjoining teeth by a dental wedge. A dental matrix, typically a metal band, is then inserted around the tooth to hold filler material.
Most wedges are of a basic trihedron shape and taper to a point. In use, the wedge is inserted in the gap between adjacent teeth to further separate them so that repairs can be performed. The amount of separation between teeth depends on the size of the wedge which is used.
Since the dental wedge is limited in length, a plurality of wedges must be available to accommodate all the different sizes needed for the different intertooth gaps and the amount of separation which may be needed. Examples of such wedges include the dental separating wedge disclosed in U.S. Pat. No. 3,000,079 and U.S. Pat. No. 3,636,631.
Other types of dental wedges include the trihedron dental wedge of U.S. Pat. No. 3,890,714, which is characterized by a plurality of serrated openings.
U.S. Pat. No. 4,259,070 teaches a variation on the trihedron wedge wherein a pair of disposed interfitting circular-bodied wedges are interposed between teeth. U.S. Pat. No. 2,867,905 also discloses a trihedron type dental wedge having a sheath. U.S. Pat. No. 1,806,718 discloses a dental wedge comprised of a plurality of tapered sections used in a fashion similar to those described hereinabove.
Other dental wedge embodiments include the tapered C-shaped dental wedge disclosed in U.S. Pat. No. 4,578,035; the dental matrix of U.S. Pat. No. 532,722; and the tooth-spreader wedge of U.S. Pat. No. 819,136.
Dental wedges disclosed in the prior art are incapable of varying the tooth separation once the wedge is put in place between adjacent teeth. This has not been a problem with conventional amalgam fillers, as such fillers are somewhat viscous and can be packed against the matrix, slightly expanding the matrix toward the adjoining teeth. When the matrix and wedges are removed, the adjoining teeth will return and again contact the adjoining teeth at the top surface.
However, with newer composite type fillers there is insufficient viscosity to allow for packing. Consequently, when a conventional dental matrix and wedges are removed, a gap will remain between teeth at their top surfaces. It would therefore be advantageous to have an improved dental wedge for use with the newer composite materials. The present invention provides such a wedge which is adjustable to vary the separation between adjacent teeth.